计算字符串显示的像素

画布类实现：

public  class GrapTool
{     
    
     public GrapTool()
      {         
      }
 
      private Graphics g;
      protected Graphics G
      {
          get
          {
              if (g==null)
              {
                  Bitmap bm = new Bitmap(800, 15);
                  g= Graphics.FromImage(bm);
              }
              return g;
          }
      }
      private Font f;
      protected Font F
      {
          get
          {
              if (f==null)
              {
                  f=new Font("Arial", 8);  
              }
              return f;
          }
      }


      public  float GetWidth(string src)
       {        
             SizeF siF= G.MeasureString(src,F);           
             return siF.Width;            
       }
}

itextsharp实现:

BaseFont bf = BaseFont.createFont(BaseFont.HELVETICA , BaseFont.CP1252 , BaseFont.NOT_EMBEDDED);
float pageLen = bf.getWidthPoint("abc 123 abc 123" , 12);